Impact of white noise on sleep quality across age groups and in critically ill/non-critically ill patients: A systematic review and meta-analysis of randomized controlled trials
- Forfatter(e)
- Ding, Y., Sun, X., Yin, J., Wang, Z., Zhang, X., Zhang, D., Zhu, L., Zhang, H.
- År
- 2025
- Tidsskrift
- Sleep Medicine
- Volum
- 136
- Sider
- 106869
- Kategori(er)
- Søvn (inkl. søvnforstyrrelser)
- Tiltakstype(r)
- Avspenningstiltak (dyreterapi eller avspenning knyttet til medisinske prosedyrer)
- Abstract
BACKGROUND
Sleep exerts modulatory effects on the neuroendocrine system, immune homeostasis, and psychological cognitive functions. As a non-pharmacological intervention, white noise has garnered widespread attention for its potential to improve sleep through mechanisms such as acoustic masking effects and neuromodulation. However, its efficacy varies across different age groups (infants, adults, older adults) and clinical settings (intensive care units vs. non-intensive care units), and a systematic evaluation of these effects remains lacking.
OBJECTIVE
To evaluate the effect of white-noise therapy on sleep-quality improvement in different age groups (0-3 years: infants and toddlers; 18-64 years: adults; >=65 years: older adults) and clinical settings (intensive care unit vs. non-intensive care unit).
DESIGN
Systematic review and meta-analysis.
METHODS
We will search randomized controlled trials (RCTs) published up to February 15, 2025, in databases including PubMed, Embase, Web of Science, the Cochrane Library, and CNKI. Studies investigating the impact of white noise on sleep quality will be included, with primary outcomes encompassing the Pittsburgh Sleep Quality Index (PSQI), total sleep time (TST), sleep efficiency (SE), number of awakenings (NOA), and wake after sleep onset (WASO). Two investigators will independently screen the literature, extract data, and assess the risk of bias using the Cochrane Risk of Bias tool. Meta-analyses will be performed using RevMan 5.4 and Stata 18.0, with treatment effects expressed as mean difference (MD), standardized mean difference (SMD), and corresponding 95 % confidence intervals (CIs).
RESULTS
A total of 12 RCTs involving 1301 participants were included in the analysis. The study population comprised 356 infants and young children (aged 0-3 years), 648 adults (aged 18-64 years), and 297 older adults (aged >=65 years). Among them, 544 were critically ill patients (emergency intensive care unit, coronary care unit, and intensive care unit), and 401 were non-critically ill patients (admitted to general wards or non-hospitalized settings). Meta-analysis revealed that, in the infant and young-child population, white noise significantly prolonged 24-h TST [MD = 137.51 min, 95 % CI (67.80, 207.23), P = 0.0001], whereas it showed no significant effect on nocturnal 12-h TST [MD = 102.56 min, 95 % CI (-39.91, 245.04), P = 0.16]. For SE, white noise did not improve 24-h SE [MD = 7.77 %, 95 % CI (-12.48, 28.39), P = 0.46], but it significantly increased 12-h SE [MD = 6.62 %, 95 % CI (1.72, 11.52), P = 0.008]. In addition, white noise reduced the NOA during both the 24-h period [MD = -19.42, 95 % CI (-35.21, -3.64), P = 0.02] and the 12-h nocturnal period [MD = -1.83, 95 % CI (-3.12, -0.54), P = 0.006]. However, no significant effect was observed on 24-h WASO [MD = -8.65 min, 95 % CI (-27.33, 10.02), P = 0.46]. In the adult and older adult patient populations, white noise significantly reduced PSQI scores, both in adults [MD = -3.70, 95 % CI (-4.90, -2.50), P < 0.001] and in older adults [MD = -2.71, 95 % CI (-4.98, -0.44), P = 0.02]. Across different clinical settings, a significant reduction in PSQI scores was also observed following white noise intervention, both in patients within intensive care units [MD = -4.04, 95 % CI (-6.35, -1.73), P < 0.001] and in non-intensive care unit settings [MD = -2.61, 95 % CI (-3.84, -1.38), P < 0.001]. Sensitivity analysis indicated substantial heterogeneity in PSQI scores among adult patients. However, a leave-one-out analysis demonstrated that the direction of the pooled effect size remained unchanged, consistently supporting the efficacy of the white noise intervention. Furthermore, due to the limited number of included studies for the respective outcomes in infants and young children children, older adults, and ICU/non-ICU patient subgroups, no further sensitivity analyses were performed.
CONCLUSION
In the infant and toddler population, white noise was found to be beneficial in extending 24-h TST, improving 12-h SE, and reducing the NOA over both 24-h and 12-h periods. However, it did not yield significant effects on extending nocturnal 12-h TST, improving 24-h overall SE, or reducing WASO. Among adult and older adult patients, white noise significantly lowered PSQI scores, indicating effective improvement in their sleep quality. Furthermore, across different clinical settings, white noise consistently demonstrated a significant reduction in PSQI scores for both intensive care unit and non-intensive care unit patients. Nevertheless, this study is limited by the heterogeneity of the included research and methodological quality, underscoring the need for further high-quality studies to comprehensively investigate the impact of white noise on sleep quality across diverse populations.